This invention relates to a method of visually displaying a multi-dimensional spatial distribution of particles obtained by a measuring device such as a particle analyzing device on a plane and, especially, to such method of displaying a time-related change of a three-dimensional spatial distribution.
For example, when a specimen prepared by extracting only leukocytes from blood is passed through a flow cytometer to measure forward and sideward scattered light intensities of each blood-corpuscle and the measured values are plotted on a two-dimensional rectangular co-ordinate plane having the forward and sideward scattered light intensities as its abscissa X.sub.1 and ordinate X.sub.2, respectively, such a distribution diagram as shown in FIG. 1 is obtained. Since a number of dots in this diagram correspond respectively to the measured corpuscles, the frequency distribution thereof is presumable from the density of the dots. However, if a third axis is established for the frequency, a three-dimensional distribution is obtained and it can be displayed on a plane as a set of sectional views along some planes normal to any axis or a solid diagram such as a topograph. An example of this method is disclosed in Japanese opened patent gazette No. S63(88)-222239 as a method of displaying a time-related change of a frequency distribution of particle volume.
However, a multi-dimensional distribution higher than three-dimension is theoretically possible also since there are more measurable characteristics of the particles. Although such multi-dimensional distributions, especially, those including time as a parameter, are important, it has been a very difficult practice to display them on a two-dimensional display screen or recording paper and no method has been proposed heretofore for this purpose.
Accordingly, an object of this invention is to provide a method of visually displaying a time-related change of a spatial distribution of three or more dimensions in simple and plain fashion through simplified data processing.